This question never seems to come up for some reason but is obviously something even people with hundreds of games don't know how to do... how do you close infantry to close range to make use of short range weapons?

Let's collective come up with ways to help players better utilize units with smgs and other assault weaponry.

I think you firstly need a map which allows you to flank, so to have at least 2 "entrances" to the frontline which your opponent won't be able to cover with great effectiveness at the same time. If you're playing a tunnel map, you need to push with an allie on one corridor to outnumber 1 opponent, and then find a "side-entrance" to your direct opponent's tunnel.

As nami said, using units to bait your enemy's attention is a great way to do so: you might know if he has recon, so you might then move some forces next to the front to make your enemy turn his defences towards that side, and then attack him with something else from a different direction: you might lose a part of your forces, but if you well manage your units you'll probably kill some of your targets. (Seems quite an abvious solution, but maybe sometimes people are too attached to their units they just don't wanna lose them).

To close in i think smoke can be an option: if you don't have recon, sending infantry might still reveal you where the mg/anti inf is allowing you to retreat quite safely and just reinforce your squad. Then you might have a second try, covering mg/anti inf with smoke, then trying to rush it and throw nade, or try to find the AT, destroy with inf and just roll over with a tank.

Same thing can be done using smoke on AT and sending a tank which will have a consistently decreased chance to get hit while clearing all the other defences on the field.

It's pretty obvious to say, but attacks will work good if you just destroy the right objective with low effort, and then send in the bigger attack to clear the remaining stuff with those units your enemy has no longer a counter for.

If you're in an infantry only engagement and you need to get closer i'd reccomand using at least one long range unit as support: allies rifle nades are good to inflict the first losses at long range and, even when they won't hit, they'll probably cause the enemy squad to panic and get out of cover. With the right timing you'll create a small window for your close quarter unit to close in. Using suppression abilities or units on enemy squads can be very useful to make your close quarter unit's path safer (i'm thinking of riflemen bar's ability, but even deploying mg squads on the right place and with the right timing).I wouldn't reccomand smoke in theese inf-only engagements since it will just warn your opponent you're trying to get closer and he will just relocate taking advantage of the cover you just gave him (smoke can be a double edged tool in battle).

A less used tactic is temporarily buffing your infantry with officer (or doctrinal) assault ability, which gives great bonuses on accuracy and suppression received by your infantry (probably gives sprint too) so you're less likely to lose men on the way to the target.